Category Archives: Microcontrollers

Blinky AVR Earrings

Blinky AVR Earring

Look what just arrived in the mail– Blinky AVR Earrings!

Blinky AVR Earrings

Not long ago, Rick posted on twitter about the ATtiny84 blinky earrings he had made, inspired by my voltage regulator earrings (which I now fasten on with the appropriate phillips screw).

Four blue LEDs blink in sequence, powered by a CR1220 battery. The board is traditional OSHPark purple, with an ISP header for convenient reprogramming. They’re lighter than they look and quite comfortable.

Thank you, Rick! I know what I’ll be wearing to Maker Faire!

From the Mailbag: Interactive Game of Life

Game of Life by Forrest

Forrest shared these pictures of his Interactive Game of Life build.

I bought the project to help expose my two grandsons to electronics and learn how to build circuit boards.  Dan my 10 year old did one board all by himself just using your instructions. Josh my 14 year old did more than half of the boards and I finished them up because I only have the kids for limited time periods. I am so proud of them. Josh complete understands how the Game Of Life works…I don’t  HA!  We are planning on adding a instruction board to the bottom of the display so other kids can have fun.

I have a CNC router and built the frame.  The boards are screwed onto a piece of 1/4″ plywood which floats in the frame.  Not glue in.  I machined a loose slot around the inside frame pieces.  That way I can take the frame apart and easily change out of a board if necessary.  It has been so much fun to build and you have SUPER service.

We thank you so much and would like to build more projects that you may come up with.  As soon as I get more time with Dan we are going to build the clock.

He also shared his case design (105 kb dxf). Thank you for sharing your time and skills with your grandkids, and for sharing your pictures and design with the rest of us!

Meggy Jr RGB + WaterColorBot

Meggy Jr RGB controlling WaterColorBot

Our friend Schuyler hooked up our Meggy Jr RGB hand-held video game platform up to control the WaterColorBot. He wrote on twitter:

I got the @EMSL Meggy Jr RGB working with the @MakerSylvia WaterColorBot. My code is here. https://github.com/docprofsky/meggyjr-cncserver.

WaterColorBot art made using Meggy Jr RGB

The output looks great, too. Thanks for sharing your code, Schuyler!

From the mailbag: DIY holiday lights

Chris wrote in:

I wanted to say thank you for writing your blog and the products you’ve created.  I used both to make my christmas lights this year.  Couldn’t have done it without you.

 

I used an ATmega xx8 mini dev kit programmed with an ISP shield to control a series of WS2811 LED pixels to make beautiful light. The controller is designed to be standalone, not part of a bigger system. I used a BCD thumbwheel switch to select up to 10 looks.

 

We can give credit to the FastLED Library team for the heavy lifting.  The case is from your friends at Adafruit. The target boards don’t quite fit in the Adafruit cases.  Thankfully ya’ll had the schematic PDFs posted and I saw I could literally cut corners to make them fit.

Back to why I appreciate what you do so much, growing up my dad tried to teach me about electronics.  He was putting motorola 6802 CPU’s in Sperry New Holland hay bale wagons.  Unlike how easy we have it today with Arduino he had to program in assembly…

 

I got a degree in Theatre and loved doing sound and lighting design.  So I really love the art you put into your technology. I’ve built many of your kits.  My favorite are the interactive LED panels.  Blinking lights!  I like to put them behind the ikea glass “white boards” so my ideas really shine when I write them down.  I’m looking forward to seeing what you do in 2015!

Introducing WaterColorBot 2.0

WaterColorBot 2.0

We are very pleased to introduce something that we’ve been working on for most of this year: WaterColorBot version 2.0!

WaterColorBot 2.0

The WaterColorBot is our collaboration with Super Awesome Sylvia: A friendly art robot that moves a paint brush to paint your digital artwork onto paper, using a set of watercolor paints.

Version 2.0 brings it to the next level with some greatly improved hardware. First and foremost, the carriage that holds the brush has been completely redesigned:

WaterColorBot 2.0

The carriage on the original WaterColorBot was made from laser-cut plywood, with nylon bushings and two simple delrin strips that formed the vertical flexure translation stage. (You can read more about the original carriage here and here.)

The new carriage consists mainly of two pieces of metal. The center block of anodized aluminum is CNC milled, and houses crossed linear roller bearings. Wrapped around that is a laser-cut and formed aluminum part that mounts the brush-lift motor, cable guide, and the flexure stage.

WaterColorBot 2.0

The new flexure stage is built with two custom flex circuit boards, used in this case as mechanical flexures. Each board consists of a very thin (0.1 mm, 4 mil) Kapton sheet with a thin fiberglass (G10/FR4) stiffener on its center section. With the two ends of each sheet clamped rigidly and the stiffener in the center, each flex circuit is to flex only along two well-defined lines. And with two boards, it forms a neat parallelogram linkage, without the slop that one might encounter in multi-part hinges. The net effect is that this new flexure stage has remarkable stiffness compared to the old design.

WaterColorBot 2.0

That stiffness, combined with the improved performance of the linear ball bearings makes this a more precise WaterColorBot. Not that you could even detect the improvement with a fat brush and watercolor paints, but things are looking quite good even with using ultra-fine point drawing pens, as you can see above.

WaterColorBot 2.0

The second major change is to the system of Spectra cords that the stepper motors control in order to move the carriage. Previously, the cords were guided around 11 plain bearings (stainless steel solid rivets) and 3 ball bearings.  We’ve simplified this into an arrangement of just 8 ball bearings— four for each motor. The ball bearing pulleys have also been updated to use wide V-groove bearings that are easy to wrap the cords around.

Which brings us to the third (and last) major change. Thus far, WaterColorBot kits have shipped “some assembly required” — with all the major components built, but the cord lacing left to the end user. As of 2.0, WaterColorBot kits now come fully assembled and tested. That doesn’t make them any less hackable, but it does mean that you can get up and running faster.

WaterColorBot 2.0

Version 2.0 includes the same CNC machined aluminum winches that we introduced back in August. Tiny detail: we’ve carved a subtle indentation into the wood around the winch that makes them a little easier to turn by hand.

WaterColorBot 2.0

The new WaterColorBot kits will begin to ship right after Thanksgiving. And a bonus present for the holiday season: Version 2.0 is priced the same as the previous version, it’s just a whole lot more awesome per dollar.

Mega Menorah 9000!

MM9k

MM9k  MM9k

Introducing our newest Hanukkah menorah kit: Mega Menorah 9000!

This is a great new easy soldering kit to make a handsome and decently-sized menorah. Once built, it stands just over 6 inches (15 cm) tall, and is 7.5 inches (19 cm) wide.

It’s USB powered, USB programmable with a built-in interface based on the Adafruit Trinket, and features 9 discrete RGB LED “pixels” that can produce all kinds of bright colors. Flickery flame effects built in too, of course.

MM9k

One of the cool things about this kit is that it has a unique “Trompe-l’œil” circuit board design that gives some illusion of a rounded 3D surface. As you can see above, it’s actually flat as a board.

To make it, we started with a 3D CAD model of what we wanted the circuit board to look like. The outer contours of the model became the outline of the circuit board. We then rendered the CAD model, and used our StippleGen 2 software to convert the resulting image into a vector stipple drawing— one that could eventually be converted into the artwork for the circuit board. All together it’s over 9000 stippled dots of black silkscreen! (To be more specific, there are roughly 17,000 dots on each side.)

MM9k FAQ: OK, but isn’t the name “Mega Menorah 9000″ perhaps just slightly on the excessive side?
Yes, we must (grudgingly) admit that it is. It just slipped out when we were trying to come up with a working title for the project — a name that meant “better than deluxe” so as to distinguish this model from our old favorite Deluxe LED Menorah Kits.
Alas, it was funny. And so it stuck. And now, it’s too late.

MM9k  MM9k

There are two circuit boards in the kit. The “top” PCB is shaped like a menorah and the components (mainly just the nine WS2812-style LEDs) are for the most part hidden on the back side.

The base circuit board has rubber feet, the control buttons (color, night, reset), an ATtiny85 AVR microcontroller, USB power/programming jack, and a programming indicator LED. The circuit is actually an implementation of the Adafruit Trinket, which allows for reprogramming the microcontroller without requiring any hardware other than a regular USB cable.

MM9k FAQ: Why is there a binder clip there?
It’s an assembly jig that helps to align the parts in place so that it’s easy to build and looks neat. We’ll write more about it later.

MM9k

And, wow does this thing do colors! The nine WS2812-style individually addressable RGB LEDs in 5 mm packages, look reminiscent of candle flames, but can be tuned to just about any color in the rainbow. From a control standpoint, it’s awfully nice that they’re managed by just a single pin of the microcontroller, and have the built-in ICs to handle colors and dimming.

Mega Menorah 9000 begins shipping this week.

Robot heart

For Halloween this year, I went as a robot, wearing a silver dress with a slowly pulsing LED heart glowing visibly under the fabric.

Untitled

The LED is a one watt white LED, which we’re running at about 50 mA. It has a wide viewing angle, and the star-shaped mount lies conveniently flat. The LED is wired up to the PCB with a pair of twisted magnet wires. Magnet wire is flexible and thin, which makes it hardly noticeable under clothing. It is controlled by ATtiny2313 (running the code from our Mac sleep light pumpkin project) and powered by three AAA batteries. The PCB corners were rounded off so it wouldn’t be stabby.

Untitled

The dress was fully lined, which made it very convenient for mounting electronics. I pinned a makeshift pocket onto the liner, and tucked the battery holder and PCB in the pocket. I could feel the battery holder switch and turn it on and off through the fabric.

Untitled

The LED was taped to the dress liner with medical tape to hold it in place. An extra piece or two of tape held the wires to make sure there was appropriate slack for movement. (A note on tape: use the good stuff. The cheap paper tape in the off-brand first aid kit only stuck to itself and the magnet wire. 3M plastic medical tape worked great and came off easily.) This makes it easy to disassemble after Halloween.

LED heart


You can find more costume projects in our Halloween Project Archive.